SAP HCI is designed as Integration System-as-a-Support (PAAS) which really helps to combine multiple independent techniques/apps for a company system. HCI can perform Cloud to Cloud, Cloud to On-premise, On-premise to On-premise and Hybrid product. HCI offers Adapters (Connectivity alternatives) for example: Cleaning soap Adapter, IDoc, HTTP, Mail, SFTP,Ariba, oData. https://s4hanacloudfaq47036.bloguetechno.com/hana-cloud-integration-63637890